New Steam Client Update

Valve released a new Steam client update, a pretty big one as well. To apply the update, click the File menu inside of Steam and then select 'Check for Steam Client Updates...'. New Features and UI updates:

Steam Screenshots
 * Added support for Steam Screenshots. Press F12 while in any game that runs the Steam Overlay to take screenshots, then publish them to your Steam Community profile, or anywhere else on the web. Each user is allotted 1 GB of Steam Cloud storage for screenshots.

Library Search capability and related navigation updates
 * Added Search capability to the library for quick filtering of your list. Press Tab to move focus to and from the search field, press Esc to clear the search.
 * Moved access to all library sub views (Games, Media Tools, Downloads, etc.) into the library's dropdown control

Voice quality improvements
 * Changed microphone voice input from 11 kHz to 16 kHz
 * Changed voice output from 8 kHz to 16 kHz
 * Fixed the settings-dialog microphone test to correctly re-init the calibration client if the active voice device changes
 * Reduced voice prefix buffer size from 200 to 100 ms, but increased trailing from 200 to 400 ms - reduces latency when transitioning from silence to active voice, but still should keep it from sounding like chat is cutting out mid-sentence
 * Increased thresholds for voice activity detection, making it less sensitive
 * Increased amount of gain applied to voice
 * Changed disconnect message when a friend ends a voice call to ' has ended the call'
 * Windows: Fixed microphone to reinitialize correctly if Windows signals that a device in the system has changed
 * Windows: Changed voice output device for Steam to be the default communication device

Web addresses
 * Added an option to display the client's URL address bar, and turned it off by default, given its limited utility
 * Web views now include a "Copy Page URL" command in the context menu, to copy the page's web address to the clipboard

Game invites
 * Moved game invites from friends outside of the chat stream, into their own panel in the chat dialog for improved discoverability

Account security
 * Added password strength meter to the Change Password wizard
 * Added a prompt to choose a new password if you've recently had Steam Support change your password on your behalf

General bug fixes
 * Fixed game invites not working from lobby-based games
 * Fixed games not launching automatically after resolving a cloud conflict
 * Fixed download rate sometimes erroneously reporting very high speeds
 * Fixed a crash on startup or when viewing Games page
 * Fixed client hang which could occur while hovering on links in any HTML-based display area
 * Corrected check box states in the Friends window menu to properly remain in sync
 * Fixed bug where some downloadable content was not downloaded until the client was restarted
 * Fixed a rare and small, but steady memory leak caused by the Steam Overlay in some full screen D3D10/D3D11 games
 * Mac OS X: Fixed a problem where attempting to resume a paused/interrupted download could always report